The duration of antibiotic therapy in bacterial meningitis is a controversial issue. Antibiotic regimens have changed over time along with the criteria used to determine the ideal antibiotic therapy duration. The authors aim to make an historical overview on this matter and simultaneously add the evidence of recent studies, pointing out some issues in results interpretation, namely, their design and the associated demographic and epidemiological questions. Clinical assays on this subject, with statistically significant results, are quite recent. Most of the scientific knowledge has been acquired empirically through the times. The actual investigation paradigm, in what concerns to antibiotic therapy in bacterial meningitis, lays on the dichotomy: "short versus long duration regimens". Nevertheless, so far, the existing studies have not completely cleared this doubt. Thus, despite some evidence suggests that short duration antibiotic regimens are effective for some patients, in patients with severe disease presentations or with other morbidities its use may be questioned.